This guide covers What Is a Business Day? | TimeFlow — what it means, how it works, and how to use it. The explanations below are followed by worked examples with real dates and real times, a set of frequently asked questions, and links to the tools that do the calculation for you: the time zone converter, the world clock, and the UTC converter. Where a number is given — an offset, a date, a count — it is computed from the IANA Time Zone Database for the date stated, not copied from a table that may be out of date.

Try the tool: Time Zone Converter — convert any time between any two cities, with the daylight saving rules for the date you choose.

A business day is a day on which businesses and government offices are normally open — usually Monday to Friday, excluding public holidays. Saturday and Sunday are not business days, and neither are public holidays like Christmas Day or New Year's Day.

The concept matters because deadlines, deliveries and contracts are often counted in business days, not calendar days. 'Delivery in 5 business days' means five weekdays, so an order placed on a Friday arrives the following Friday, not the following Wednesday. A contract that gives '10 business days' notice' gives two full working weeks, not ten days.

What counts as a business day varies by country and industry. In most of the Middle East, the working week is Sunday to Thursday, so Friday and Saturday are the weekend. In Israel the working week is Sunday to Friday. In finance, a business day also excludes bank holidays, which differ by country. And in some industries — retail, hospitality, healthcare — Saturday is a normal working day, so 'business day' has to be defined in the contract.

Counting business days is a calendar problem, not a guess. The reliable way is to count the weekdays in the range and subtract the public holidays that fall on weekdays. That is what the business days calculator on this site does — and it is why the answer for a given month depends on which year it is, because the same month has a different number of weekdays in different years.

In practice

The definition sounds simple — a day on which business is conducted — but the details vary. In most of the world, a business day is a weekday that is not a public holiday. In the United States, that means Monday to Friday excluding the eleven federal holidays. In the Middle East, the working week is Sunday to Thursday, so Friday and Saturday are not business days. In Israel, the working week is Sunday to Friday, with Saturday as the day of rest.

The distinction matters because deadlines are written in business days. A contract that says 'delivery within 10 business days' means something different from 'delivery within 10 days', and the difference is the weekends and holidays in between. Ten business days from a Monday is a fortnight later; ten calendar days is ten days later. The gap grows when a public holiday falls in the middle.

Banks, courts and government departments all run on business days, and their calendars are the ones that count. A payment that takes 'three business days' to clear will take five calendar days if it starts on a Friday. The business days calculator counts the business days in any range, with the US federal holidays subtracted and your own holidays added, so you can check a deadline before you promise it.

The numbers: the year 2026

2026 is not a leap year: it has 365 days, 52 full weeks and one extra day, and 53 ISO weeks (because it starts on a Thursday). There are 261 weekdays in the year and 104 weekend days. The next leap year is 2028, and the one after that is 2032; the century year 2100 will not be a leap year, because it is divisible by 100 but not by 400. 1 January 2026 was a Thursday, and 31 December 2026 will be a Thursday.

The extra day is the reason the calendar shifts: because 365 days is 52 weeks and one day, every date falls one weekday later the following year — two days later after a leap year. That is why your birthday is on a different weekday almost every year, and why the calendar repeats every 28 years in most cases. The week number finder gives the ISO week for any date, the date calculator works out what date it is a number of days from now, and the days between dates calculator counts the days between any two dates.

2027 is also not a leap year: it has 365 days, 52 ISO weeks, and 261 weekdays. It starts on a Friday and ends on a Friday. The next leap year after 2026 is 2028, which will have 366 days and 262 weekdays. The business days calculator counts the business days in any year, with the public holidays subtracted.

Key facts

  • A normal year has 365 days and a leap year has 366, with the extra day on 29 February.
  • A year has 52 full weeks and one extra day — or two in a leap year.
  • The Gregorian leap year rule: divisible by 4, except centuries, except centuries divisible by 400.
  • A business day is a weekday that is not a public holiday — and the holidays depend on the country.
  • In the ISO week system, the week starts on Monday and the first week is the one containing the first Thursday.

Frequently asked questions

What is a business day?

A day on which business is conducted — in most of the world, a weekday that is not a public holiday. In the US that means Monday to Friday excluding the eleven federal holidays.

Is Saturday a business day?

Not usually. In most countries the working week is Monday to Friday, so Saturday and Sunday are not business days — but in Israel Saturday is a working day, and in some industries Saturday is a business day.

Is a public holiday a business day?

No. A public holiday that falls on a weekday is subtracted from the business day count. That is the difference between business days and working days.

How many business days are in a week?

Five, in a normal week with no public holidays. A week with a Monday holiday has four business days.

How do I count business days between two dates?

Count the weekdays in the range and subtract the public holidays that fall on weekdays. The business days calculator does it for any range.

How many weekdays are there in 2026?

261 weekdays and 104 weekend days, out of 365 days in total. 2026 is not a leap year. The business days calculator counts the business days, with the public holidays subtracted.

What is the time difference between London and Tokyo?

Nine hours in January 2026: London is UTC+00:00 and Tokyo is UTC+09:00. In July it is eight hours, because London moves to UTC+01:00 while Tokyo stays on UTC+09:00. The time zone converter gives the difference for any two cities and any date.

Related pages

Sources

  • IANA Time Zone Database, via Node.js Intl (Intl.DateTimeFormat with timeZone) — offsets, daylight saving dates and local times in this article were worked out from the IANA database, not typed from memory.
  • TimeFlow's own time-zone data (data/cities.ts, data/dst.ts), computed from the IANA database.
  • Time zone rules and offsets: the IANA Time Zone Database, as applied by this site's tools. Offsets and daylight saving dates on this page are computed from the database for the dates stated.
  • TimeFlow's time zone converter, world clock and UTC converter — the live tools behind the numbers on this page.
  • Time-zone and daylight saving rules are set by governments and can change. For flights, deadlines and meetings that cannot move, confirm the time with an official source.